Some misc River/Water questions

This time around I decided to use the water creation tools instead of drawing my rivers onto the terrain and I have a few questions I’m struggling to find answers for.

  1. Why do the reach character rivers stop so far short of their upstream “origin” points? You can see the channels for the river in the terrain but the rivers themselves don’t start until further down the hills.

  2. Is there a way to export just the rivers as a mesh? That was easy to do with hand drawn rivers but I’m not finding a way to make it happen with these rivers. Alternatively, any tips on how to get the river info into Unreal for shading?

  3. How can I make these rivers meander a bit more? They look awfully straight in many places and I would like to vary it up a bit. I’ve played with the various sliders in the Meander section of the Reach Character Generator but I can’t seem to make any significant changes to what’s there already.

Thanks guys.

Here’s a pic of the terrain and an overview of my node graph:


Nice to see you’re trying out new stuff, that’s always a good thing :slight_smile:. Regarding your questions:

1. Change river spawn position

This has to do with the Headwater area parameter in the Create Water device. This parameter determines how much area, in square kilometres, a river needs as drainage area, before it can spawn. If you decrease the parameter’s value, less drainage area is needed and therefore rivers can spawn “higher up”. See the gif below.

2. Mesh export

I would recommend the new Meshify device, if it weren’t for the fact, this device will only output at low resolution when using a uniform grid for some reason…? @Stephen, is this the correct behaviour? So, instead, grab the Mesh Output device, and change its device version to the 3025 version.

This device can then export your water mesh, simply by connecting the water output of the Create Water to it.

3. Meandering

Meandering is only achieved in rough terrain. In your setup, the terrain is really smooth, due to the Erosion device higher up in your graph. See the example below, the less even the terrain is, the more meandering is achieved. The frequency/feature scale of these roughnesses also are important, as high frequency bumps give way to small meanders, in contrast to low frequency bumps.

I hope this helps you!


Thank you! I will give these tips a try!

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